[A case of bilateral MALT (mucosa-associated lymphoid tissue) type conjunctival malignant lymphoma].

A case of bilateral MALT (mucosa-associated lymphoid tissue) type conjunctival malignant lymphoma is reported. The patient, a 32 year old female, was referred to our hospital with the diagnosis of allergic conjunctivitis. We performed histopathological, immunohistochemical, and molecular genetical examination. The histopathological findings showed proliferation of CCL (centrocytelike) cells, lymphoepithelial lesion, and follicular colonization. Monoclonality of the tumor cells was revealed by molecular genetical analysis. On the basis of these detailed examinations, the patient was diagnosed as having MALT type malignant lymphoma. MALT type malignant lymphoma was first described by Isaacson in 1983. Both histological and clinical features are characteristic and quite different from other lymphomas. Some patients are affected bilaterally. Immunohistochemical and molecular genetical examinations in MALT type malignant lymphomas were found to be useful.